1. Field of the Invention
The invention relates to chemical apparatus for the automatic analysis of biological fluids, and more particularly, to cover means for cooperating with analysis slides in an incubator of such apparatus to control evaporation of sample fluids carried by the slides.
2. State of the Prior Art
In recent years, a number of automated systems have been developed for carrying out quantitative chemical analyses of sample fluids. In the aforementioned U.S. patent application Ser. No. 855,124, there is described a chemical analyzer in which a sample fluid is metered onto an analysis slide which is then transferred into an incubator. The incubator comprises a temperature-controlled chamber having a plurality of transfer locations wherein slides may be transferred into or out of the chamber; conveyor means rotatable in the chamber about a horizontal axis and having a plurality of slide-holding means for releasably holding the slides; and drive means for effecting movement of slides in the conveyor means within the chamber for positioning the slides for transfer at one of the transfer locations. This incubator, however, is not suitable for slides having fluids remaining in liquid form on a surface of the slide, since the slides are rotated through a vertical position in which the fluid would be spilled from the slide. The slide-holding means comprises a spring which cooperates with the slides to retain the slides in position on the conveyor.
U.S. Pat. No. 3,574,064, to Binnings et al, discloses apparatus in which glass slides are fed from a single supply station onto a turntable. Slides carried on the turntable are moved past a metering station, and then through wash and incubation stations spaced around the periphery of the turntable. Slides processed by the apparatus are ejected from the turntable into a slide receiver adjacent the slide supply station. There is no provision for automatic analysis of the processed slides, and they must be manually removed from the slide receiver for examination under a laboratory microscope. Further, there is no suggestion of a cover means for protection of the fluids on the slides.
An incubator, for use with analysis slides which are horizontally disposed in vertically-spaced slots in the incubator, is disclosed in RESEARCH DISCLOSURE, Vol. 175, November, 1978, Publication No. 17,569, published by Industrial Opportunities Limited, Homewell, Havant Hampshire, P09 1EF, United Kingdom. There is no suggestion in this publication, however, of means for controlling evaporation of fluids on analysis slides.